Compensated expansion joint



NOV. 4, 1952 H, A 'ALTORFER '2,616,255

COMPENSATED EXPANSIONA JOINT Fled-Aug. 26, 1948 Patented Nov. 4, 1,952

UNITED STATES PATENT OFFICE 2,616,255 COMPENSAITED EXPANSION JOINT Hans A. A1torfer,'WauWatosa, 'Wis., 'assignor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis.,a .corporation ofsDelaware Application August-26, 194,8., seriarNo. 46,314

(Cl. .6D-39.32;)

,1.0 Claims. 11

This invention relates `f renerally to fluid vcon# .ducting systems embodying a-source of 'high tem-rv.

perature `elastic fluid and 'a 4fluid expanding means exhausting `-hotelastic Ahuid at ya relatively -low pressure, and more -par'ticularly -to means.

'for effectively minimizing stresses Ls'et lup Iin an exhaust fluid confining portion of the 'system by..

axially acting forces produced by changes in `the temperature and pressure of the hot, low pres-v sure exhausted fluid confined therein. This `-ap-f plication vis a, continuationin par-t -of my appli'- 'cation Serial Number 480,497, 'led'March A25, 11943., vnow abandoned.

A practical design for such a -`system should embody :one for more fluid tight joints Ain fthe `exhaust Al'luid conductor operable to `permit` a relative expansion and contraction yof `intercon nected parts, the number aand location of the `joints being in each 4case determinable `from `Athev dimensions and -arrangementsvof suchpar-ts.` :In order lto render such'joints effective and ltoskeep.

Y.their .dimensions Within rpractical limits, Ait is necessary Yto embody in each 'joint -one or more annular sections `vhav-ing `ra relatively thin side' wall or Walls which are flexible axially without subjecting the conduit sections vvor other lparts interconnected thereby to va 'detrimental'degree of .axial thrust. Such 4jointconstructions, although operable to afsa'tisfactory degree in Lthe Vconstant temperature :and pressure type of .system, :have not :proven 'eiective in systems @handling .large quantities vof lfluid subjected to Y'large variations in fbo'th temperature and -pressure since the iresulting v'variations the temperature and :pres-5 :sure of the lhot, 'low :pressure :exhaust ffluid vpro- Another object of this invention 'is 5to-provide a. ,high temperature fluid .conducting system y.of 'the type rhereinabovetmentioned with means 'for :minimizing the `stresses set tup in interconnected, exhaust xfluid conducting .parts :by -axial1y;.acting 'f vforces and/or rendering ya Vminimum number of joints having Va minimum number Vof axiallyliexi ble vportions effective to prevent a rupture Bf such portions.

In accordance With'this invention, one or vmore ofthe above statedobjects may be readily accomplished in -a 4liuid conducting `system embodying an Aexpansion joint interconnecting adjacent, 'exv'haust fluideconducting parts for relative longitudinal expansion and contraction by connecting said conductorparts with a 4compensating means which is Ain tur-n connected with la Vpart of the system 'subjecting the compensator to the action of a fluid Whose temperature and Lpressure'are llow and high, respectively, relative to the temperature `and pressureof 4the-exl'laust fluid and lWhose pressure'increases and decreases as the pressure #of the exhaust fluid increases A'and decreases, L:re-

spectively Onftheotherhand, the compensating means maybe-connected to a part'of the system regardless -of the temperature of vthe fluid but lthe=.pressure of which is :high relative to the pressure iof the exhaust fl-uid. In addition-to :the foregoing, apparatus vembodying the invention may also include as .features thereof novel correlations of elements'which are of considerable'commercial importance in Athat they Arender the apparatus durable, lcheap -to manufacture .and `readily :applicable to lboth `new and .existing Vinstallations. i

Accordingly, .the ,invention alsoconsists of the lvarious :details .of construction, ,combinations .of .elements fand `arrangements Yof v.parts .as `is more fu'llyfset ,forth :in vthe .appended claims 4and in the detailed fdescription, `reference :being had x,to :the vaccompanying drawing showing 4several .embodimentstof .the invention -and `in which:

Fig.. .-1 `scheinatically illustrates .a continuons Vcombustionggas.turbine :system embodying the 3in- *.ventiorr;

.1F-ig. ..2 is :a :plan view .of the expansion ljoint construction .shown ,in Fig. l;

'p3 is a ipartial `section 4through the joint takenon line '11H- III of Fig. .1; :and

Fig. f4 :is @a view 4similar ito Fig. 1 showing an other embodiment of the invention.

vAs shown'in Fig. J. of :the drawing, the invention may tbe :applied to `an V.elasl'a :fluid power system vvcc,minimising anaxial .compressor l., a ccm- -bnstion Achamber 2:2 @embodying a fluid fuel burner 3 having-a acontrolvailve -4 .and .a connection ,6 vwith .a suitable `:source `of :fuel :,(not shown), .an axialeriow turbine .11 .Ydrringly connected with the compresso-rr;l.,-andy uid'conductingz-means; including a conduit :.8 :connecting the discharge :of .com

fixedly connected to the conduit II forms nov part of this invention, and a further description in this connection is, therefore, deemed unnecessary. 4

Conduit II includes an expansion joint unit I3 connecting the adjacent parts |14 and I6 of ccndu-it I-I for relative longitudinal expansion and contraction, it being understood, of course, that the remote ends of the parts I4 and IB are fixed to the structures with which they are connected; said unit comprising see Figs,l 2 and 3) conductors I1a, I8a of short axial length having substantially rigid end portions I'I and I8 firmly se.- cured to the opposed ends of adjacent parts I4 andv IG, respectively, and a flexible intermediate 4 connection 38 urges the cylinder and piston in opa posite directions and the parts I4 and I 6 of conduit I I toward each other with forces determined by the pressure of the fluid and the effective areas of the opposed piston and cylinder portions.

The pressure of the fluid iiowing through conduit I I, assuming no appreciable drop in pressure occurs in passing from the turbine I to the flanged end I2 thereof and disregarding the kinetic energy of the fluid, exerts an axial thrust on the parts I4 and I6 tending to pull apart and rupture the flexible portion of the expansion joint; the thrust in each such case being directly proportional to the cross sectional area of the part and the pressure of the iiuid flowing therethrough. For example, if the conduit II is arranged as shown in Fig. 1 and the pressure of the iiuid entering and leaving the parts I4 and I6 portion I9 rendering said end portions movable Y Ilongitudinally relative to each other, a plurality of Vcylinders 2| (only one of which is shown in Fig.,3) carried by the portion I'I for mov-ement therewith, and a piston 22 reciprocable in each of said cylinders and having a projection 23 connected to and rendering said piston movable with the portion I8.

1 The connection between each cylinder 2| and end rportion I'I comprises a x-ed bracket 24 which may bewelded or otherwise integrally secured to portionV I 'I, a longitudinally extending stem 26 on cylinder 2I having its outer end provided with a socket portion 2'I and a ball 28 disposed within said socket and having a stem portion 29v detachably connected to the bracket 24. End portion I8 `is also provided with brackets 3YI which arel connected t-o the projection 23 on piston 22 in exactly the same manner that bracket 24 is 4connected to the stem 29 on cylinder 2 I Y Flexible portion I9 comprises two axially spaced cylindrical sections 32 and 33 which are connected to each other and to the conductors I'Ia and I8a and hence to the end portions I'I and I8 by pai-rs of axially flexible annular disks 34 and 36 with each pair `of disks having their-inner peripheries sealingly secured to the spaced opposed ends of the sections and/or end portions to be connected together and having their outer peripheries sealingly connected to the axially spaced inner edges 'of a surrounding tubular element 31, as shown. This construction, which is not in itself new, is'merely illustrative of one form of flexible portion which may be employed in carrying out the invention, and itshould, therefore, be understood that neither the number nor the form of such sections is essential' since any means eiective to sealingly Vconnect the end portions I'I and I 8 for relative longitudinal movement will suiiice.

' Each cylinder 2I is providedwith a' iiuid admission connection 38 disposed between the piston 22 therein and the end of the cylinder adjacent the bracket 3 I' on end portion I8. A pipe 39 provided with branches 4I and 42 connects conduit 8, i.'e.; the discharge of compressor I, with the iiuid admission'connection 38 in each cylinder. Consequently, itshould be obvious that the admission of fluid under pressure through the thereof is ten pounds per square inch and the cross sectional area of each part is the same and equals 5,0v square inches, there is an equal and oppositely acting axial thrust of 500 pounds set up ineach part; the thrust in part I4 acting towards the left and the thrust in part I6 acting towards the right, thereby subjecting the flexible portion of joint I3 to a rupturing force of 500 pounds in addition to that produ-ced by the pressure ofthe fluid acting on the walls 34 and 36 connected with the end portions I'I and I8, respectively. An expansion joint in order to be eective as such should aiord but little resistance to relative longitudinal movements of the adjacent ends of conduit sections connected thereby, and it-should, therefore, be obvious that if such joints are constructed to resist the fluid produced axial thrusts, the joints are in most instances altogether Ato-o stiff to render them eective for the purposeI intended. Howevenrwhen-combined With an additional connecting means such as hereinabove described, the admission of iiuid under pressure to cylinder 2I produces oppositely acting compen'# .eating forces on the parts I4 and I6, thereby minimizingr or canceling thevei-ect of the iiuid pressure produced axially acting thrusts with a minimum number of parts of small size. v In this connection, it should be noted that in an elastic fluid power system of the type disclosed, variati-ons in power output are eiected by varying the heat input to the motive uuid which is accomplished by varying the quantity of fuel supplied to the combustion chamber and thereby the temperature of the motive fluid and that each increase and decrease in motive flu-id temperature 1s accompanied by a corresponding change in turbine speed which in turn produces a correspending change in the pressure of combustion supportin-g air delivered by the compressor. Consequently, it should now be obvious that since cylinder 2| is connected with the discharge of compressor I, the pressure of they fluid admitted to said -cylinder varies in accordance with the pressure of the motive fluid flowing through the parts I4 and I6 and that since the pressure of air discharged from the compressor I is always considerably higher than thepressure of the motiveiiuid exhausting from the turbine 1, the axial thrust imparted to the parts I4 and I6 by the pressure of the fluid flowing therethrough can be readily compensated for .with a compact and durable cylinder and piston construction of practical dimensions. i

Reference is now made to Fig. 4 which shows embodiment of the'invention. The system fragmentarily shown Yin Fig. 4 does not differ from the system of Fig. 1 except as now to be pointed out. In the embodiment of Fig. 4 the openings 38 of the cylinders 2l are connected by pipes 4l and 39a to the conduit 9, instead of to the conduit -8 of Fig. 1 (not shown in Fig. 4). It will be evident that the fluid pressure in conduit 9 is al-` ways high compared to the fluid pressure of the expanded exhaust gases in conduit ll. Hence the desired compensation of the expansion joint I3 is secured. The connecting pipe means between lthe cylinders 2| and the conduit 9 may, if desired, be provided with heat dissipating means such as the fins 50 here shown on the pipe 39a. It may be noted, however, thatv once the cylinders 2l are lled with gas, no further flow takes place from the conduit 9 to the cylinders 2| so that heat dissipated from the pipe means 4 I, 39a, if the pipe means is of sufficient length, may renderv special heat dissipating means, .such as the fins 50, unnecessary if it is desired to run the cylinders 2| at a temperature relatively low compared with the uid in conduit 9.

The invention is applicable to all forms of uid systems embodying an expansion joint interconnecting the adjacent ends of fluid conducting sections or parts for relative longitudinal expansion and contraction, and it should, therefore, be understood that although the invention has been illustrated and disclosed in connection with a continuous combustion gas turbine system, it is not intended to limit the invention to the exact constructions herein shown and described, as various modications within the scope of the appended claims may occur to persons skilled in the art.

It is claimed and desired to secure by Letters Patent:

'1. In combination in an elastic iluid system including compressor means for providing compressed elastic fluid, combustion chamber means, means for conducting compressed elastic fluid from the discharge' means of said compressor means to said combustion chamber means, turbine means operable by combustion gases, means for conducting combustion gases from said com bustion chamber means to inlet means for said turbine means, exhaust conductor means receiving exhaust gases from said turbine means and including opposed conductor portions connected by an axially flexible expansion joint for relative longitudinal movement, va cylinder carried by one of said conductor portions in spaced parallel relation with respect to said flexible expansion joint, a piston carried by the other one of said conductor portions and reciprocably disposed within said cylinder, said cylinder having an opening for admitting iluid under pressure to act on said cylinder and piston and thereby urge said lconductor portions axially toward each other, and means placing said opening in communication with 'said system at a place between the discharge means of said compressor means and inlet means to said turbine means.

2. In combination in an elastic iiuid system including compressor means for providing compressed elastic fluid, combustion chamber means, meansl for conducting compressed elastic fluid from the discharge means of said compressor means to said combustion chamber means, turbine means operable by combustion gases, means for conducting combustion gases from said combustion chamber means to inlet means for said turbine means, exhaust conductor means receivingA exhaust gases from said turbine means and including opposed conductor portions connected by an axially flexible expansion joint for relative longitudinal movement, a cylinder carried by one of said conductor portions in spaced parallel relation with respect to said flexible expansion joint, a piston carried by the other one of said conductor portions and reciprocably disposed within said cylinder, said cylinder having an opening for admitting fluid under pressure to act on said cylinderv and piston and thereby urgev said conductor portions axially toward eachother, and means placing said opening in com-v munication with said system at a place between the discharge means of said compressor means and inlet means of said combustion chamber means.

3. In combination in an elastic uid system in-V cluding compressor means for providing conrpressed elastic fluid, combustion chamber means, means for conducting compressed elastic uid from the discharge means of said compressor means to said combustion chamber means,vtur bine means operable by combustion gases, means for conducting combustion gases from said combustion chamber means to inlet means for said turbine means, exhaust conductor means receiving exhaust gases from said turbine means and including opposed conductor portions connected by an axially flexible expansion joint for relative longitudinal movement, a cylinder carried by one` of said conductor portions in spaced parallel relation with respect to said iiexible expansion joint, a piston carried by the other one of said conductor portions and reciprocably disposed within said cylinder, said cylinder having an opening for admitting fluid under pressure to act on said cylinder and piston and thereby urge said conductor portions axially toward each other, and means placing said opening in communication with said system at a place between said combustion chamber means and inlet means to said turbine means.

4. In combination in an elastic fluid system including compressor means for providing low temperature compressed elastic iiuid, combustion chamber means, means for conducting compressed elastic fluid from the discharge means of said compressor means to said combustion chamber means, turbine means operable by com bustion gases, means for conducting combustion gases from said combustion chamber means to inlet means for said turbine means, exhaust conductor means receiving exhaust gases from said turbine means and including opposed conductor portions connected by an axially flexible expansion joint for relative longitudinal movement, a cylinder carried by one of said conductor portions lin spaced parallel relation with respect to said exible expansion joint, a piston carried by the other one of said conductor portions and reciprocably disposed within said cylinder, said cylinder having an opening for admitting fluid under pressure to act on said cylinder and piston and thereby urge said conductor portions axially to- Ward each other, pipe means placing said opening in communication with said system at a place between the discharge means of said compressor means and inlet means to said turbine means, and means for dissipating heat from said pipe means. f

5. In an elastic fluid turbine system, a compressor, a combustion chamber, a turbine drivingly connected with said compressor, fluid conducting means including portions connecting said compressor, combustion chamber and turbine in series flow relation for supplying air to said combustion chamber and combustion products to said turbine," said fluid conducting means including a turbine exhaust portion having an axially flexible expansion joint interconnecting adjacent opposed parts of said exhaust portion for relative longitudinal movement, means for varying the heatl input to said combustion chamber and thereby the temperature and pressure of the combustion products exhausting from said turbine, a cylinder carried by one of said adjacent opposed parts, a piston reciprocable within said cylinder and carried by the other one of said adjacent opposed parts, said cylinder having an opening for admitting fluid under pressure to act on said cylinder and piston and thereby urge said adjacent opposed parts toward each other, and means placing said opening in communication with a portion of said system confining and conducting compressed unheated elastic fluid to said combustion chamber whereby the interior of said cylinder is normally subjected to the action of a fluid Whose temperature and pressure are low and high, respectively, relative to the temperature and pressure of the hot combustion products exhausting from said turbine and whose pressure increases and decreases as the pressure and temperature of the hot combustion products exhausting from said turbine increases and decreases, respectively.

6. In combination in an elastic iluid system embodying a source of compressed, low temperature elastic fluid, a variable temperature fuel burning apparatus receiving compressed elastic` fluid from said source and producing highly heated combustion gases having a temperature proportional to fuel input, a turbine receiving and expanding said highly heated combustion gases, and a conductor confining the hot combustion gases exhausting from said turbine and including opposed portions connected by an axially flexible expansion joint for relative longitudinal movement, a cylinder carried by one of said conductor portions, a piston carried by the other one of said conductor portions and reciprocably disposed within said cylinder, said cylinder having an opening for admitting fluid under pressure to act on said cylinder and piston and thereby urge said conductor portions toward each other, and means for placing said opening in communication with a part of said system confining and conducting compressed unheated elastic iiuid to said fuel burning apparatus whereby the interior of said cylinder is normally subjected to a fluid whose temperature and pressure are low and high, respectively, relative to the temperature and pressure of the hot exhaust gases and whose pressure increases and decreases as the pressureand temperature of the hot exhaust gases increases and decreases, respectively.

7 In combination in an elastic fluid system including compressor means for providing compressed elastic fluid, combustion chamber means, means for conducting compressed elastic iiuid from the discharge means of said compressor means to said combustion chamber means, turbine means operable by combustion gases, means for conducting combustion gases from said combustion chamber means to inlet means for said turbine means, exhaust conductor means receiving exhaust gases from said turbine means and including opposed conductor portions connected by an axially flexible expansion joint for relative longitudinal movement, expansible and contractible cell means having relatively movable Walls one of which is connected to oneof said conductor portions and the other of which is connected 8. to the other one of said conductor portions, said cell means having an opening for admitting iiuid under pressure to act on said relatively movable walls and thereby urge said conductor portions axially toward each other,v and means placing said opening in communication with said system at a place between the discharge means` of said compressor means and inlet means to said turbine means.

8. In combination in an elastic fluid system including compressor means for providing compressed elastic fluid, combustion chamber means, means for conducting compressed elastic fluid from the discharge means of said compressor means to said combustion chamber means, turbine means operable by combustion gases, means for conducting combustion gases from said combustion chamber means to inlet means for said turbine means, exhaust conductor means receiving exhaust gases from said turbine means and including opposed conductor portions connected by an axially exible expansion joint for relative longitudinal movement, expansible and contractible cell means having relatively movable Walls one of which is connnected to one of said conductor portions and the other of which is connected to the other one of said conductor portions, said cell means having an opening for admitting fluid under pressure to act on said relatively movable walls and thereby urge said conductor portions axially toward etch other, and means placing said opening in communication with said system at a place between the discharge means of said compressor means and inlet means to said combustion chamber.

9. In an elastic fluid turbine system, a compressor, a combustion chamber, a turbine drivingly connected with said compressor, fluid conducting means including portions connecting saidv compressor, combustion chamber and turbine in series ilow relation for supplying air to said combustion chamber and combustion products to said turbine, said uid conducting means including a turbine exhaust portionhaving an axially flexible expansion joint interconnecting adjacent opposed parts of said exhaust portion for relative longitudinal movement, means for varying the heat input to said combustion chamber and thereby the temperature and pressure -of the combustion products exhausting from said turbine, expansible and contractible cell means having relatively movable Walls one of which is connected to one of said adjacent opposed parts and the other of which is connected to the other one of said adjacent opposed parts, said cell means having an opening for admitting fluid under pressure to act on said vrelatively movable Walls and thereby urge said adjacent opposed parts to-l ward each other, and means placing said opening in communication with a portion of said system conning and conducting compressed unheated elastic fluid to said combustion chamber whereby the interior of said cell means is no1- mally subjected -to the action of a uid whose temperature and pressure are low and high, respectively, relative to the temperature and pressure of the hot combustion products exhausting from said turbine.

10. In combination in an elastic fluid system embodying a source of compressed, low temperature elastic uid, a variable temperature fuel burning apparatus receiving compressed elastic iluid from said source and producing highly heated combustion gases having a temperatureA proportional to fuel input, a turbine receiving and expanding said highly heated combustion gases, and a conductor confining the hot combustion gases exhausting from said turbine and including opposed portions connected by an axially flexible expansion joint for relative longitudinal movement, expansible and contractible cell means having relatively movable walls one of which is connected to one of said conductor portions and the other of which is connected to the other of said conductor portions, said cell means having an opening for admitting fluid under pressure to act on said relatively movable walls and thereby urge said conductor portions toward each other, and means for placing said opening in communication With a part of said system confining and conducting compressed unheated elastic iiuid to said fuel burning apparatus whereby the interior of said cylinder is normally subjected to a fluid whose temperature and pressure are low and high, respectively, relative to the temperature and pressure of the hot exhaust gases.

HANS A. ALTORFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

